package nec.aagent.core.db;

import java.sql.SQLException;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;

import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.dao.Dao;
import com.j256.ormlite.dao.RuntimeExceptionDao;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;

/**
 * Database helper class used to manage the creation and upgrading of app's
 * database. This class also usually provides the DAOs used by the other
 * classes.
 */
public class DatabaseHelper extends OrmLiteSqliteOpenHelper {
    /**
     * Name of the database file for your application
     */
    public static final String DATABASE_NAME = "location.db";
    /**
     * Any time you make changes to your database objects, you may have to
     * increase the database version
     */
    private static final int DATABASE_VERSION = 2;

    /**
     * The DAO object we use to access the SimpleData table
     */
    private Dao<LocationDb, Long> locationDao = null;
    private RuntimeExceptionDao<LocationDb, Long> locationRuntimeDao = null;

    /**
     * Singleton instance
     */
    private static DatabaseHelper INSTANCE;

    private DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    public static DatabaseHelper get(Context context) {
        if (INSTANCE == null) {
            INSTANCE = new DatabaseHelper(context);
        }
        return INSTANCE;
    }

    /**
     * This is called when the database is first created. Usually you should
     * call createTable statements here to create the tables that will store
     * your data.
     */
    @Override
    public void onCreate(SQLiteDatabase db, ConnectionSource connectionSource) {
        try {
            Log.i(DatabaseHelper.class.getName(), "onCreate");
            TableUtils.createTable(connectionSource, LocationDb.class);
        } catch (SQLException e) {
            Log.e(DatabaseHelper.class.getName(), "Can't create database", e);
            throw new RuntimeException(e);
        }
    }

    /**
     * This is called when your application is upgraded and it has a higher
     * version number. This allows you to adjust the various data to match the
     * new version number.
     */
    @Override
    public void onUpgrade(SQLiteDatabase db, ConnectionSource connectionSource,
            int oldVersion, int newVersion) {
        try {
            Log.i(DatabaseHelper.class.getName(), "onUpgrade");
            TableUtils.dropTable(connectionSource, LocationDb.class, true);
            // after we drop the old databases, we create the new ones
            onCreate(db, connectionSource);
        } catch (SQLException e) {
            Log.e(DatabaseHelper.class.getName(), "Can't drop databases", e);
            throw new RuntimeException(e);
        }
    }

    /**
     * Returns the Database Access Object (DAO) for our {@link LocationDb}
     * class. It will create it or just give the cached value.
     */
    public Dao<LocationDb, Long> getLocationDao() throws SQLException {
        if (locationDao == null) {
            locationDao = getDao(LocationDb.class);
        }
        return locationDao;
    }

    /**
     * Returns the RuntimeExceptionDao (Database Access Object) version of a Dao
     * for our {@link LocationDb} class. It will create it or just give the
     * cached value. RuntimeExceptionDao only through RuntimeExceptions.
     */
    public RuntimeExceptionDao<LocationDb, Long> getLocationRuntimeDao() {
        if (locationRuntimeDao == null) {
            locationRuntimeDao = getRuntimeExceptionDao(LocationDb.class);
        }
        return locationRuntimeDao;
    }

    /**
     * Close the database connections and clear any cached DAOs.
     */
    @Override
    public void close() {
        super.close();
        INSTANCE = null;
        locationRuntimeDao = null;
    }
}
